Gemstones are usually mounted in a device which will enhance the characteristics of the stone. The particular mounting, which may be a bezel, a basket, a pronged box, or delicate wire prongs, must be worked inwardly against the stone to retain it in the setting. The bezel has proved very useful in modern jewelry mounting. A bezel usually refers to a cup-shaped mounting having a bottom or mounting surface and perpendicular sides. The mounting surface may be either continuous or defne in the mounting surface a bore slightly smaller than the diameter of the stone to be mounted.
In order to retain the stone in the bezel, it is necessary to turn the perpendicular wall of the bezel inwardly and down so that it rests against the stone. A conventional burnishing tool, used to accomplish this working of the wall, comprises a polished hardened steel blade of substantially oval cross-section set in a handle. The blade may be slightly curved or straight. In order to set the stone, the stone is placed in the bezel against the bearing surface. The wall of the cup-shaped bezel extends upwardly sufficiently to securely retain the stone in the bezel after the wall of the bezel has been turned inwardly against the stone. In order to so turn the wall, the blade of the burnisher is urged against the top edge of the wall of the bezel turning the wall inwardly against the stone. As the edge is turned down it must also be cold worked by the conventional burnisher by a rocking or rubbing motion to compact the soft metal thus decreasing the circumference of the wall of the cup-shaped bezel so that the wall slopes inwardly against the stone. Failure to properly cold work the edge results in unsightly crimp marks and scratches about the perimeter of the mounting. To develop a skill in using a conventional burnisher requires a great deal of practice by the craftsman, not to mention material wasted in the learning process.